The use of edible oils for medicinal and nutritional purposes is well known. For example, cod liver oil is used as a nutritional supplement of vitamins A and D. Castor oil and mineral oil are used as cathartics. Marine oils and marine oil concentrates containing omega-3 fatty acids are recommended for the prevention of coronary heart disease, migraine headaches, arthritis and some allergies. Edible oils are useful as vehicles for the delivery of medicaments both topically and internally. Many edible oils are equally well known for their unpalatable taste, unpleasant odor and unpleasant mouthfeel.
The edible oils utilized in the present invention are varied and may be of animal, vegetable and mineral origin. These oils are well known ingredients in edible products such as foods and pharmaceuticals. Such oils are generally distasteful and difficult to swallow when taken orally. Oils are difficult for most people to ingest because they are greasy, oily somewhat viscous fluids. In addition, many edible oils have an unpalatable taste and unpleasant odor. Typical among the unpleasant edible oils useful for the present invention are marine oils such as fish liver oil, fish oil, whale oil, seal oil, marine oil concentrates, and marine oils containing omega-3 fatty acids; and vegetable oils such as castor oil, linseed oil and the like.
The process of obtaining marine oils, that is oil-expression, leads to the formation of amines which are in combination with the marine oil. In addition, marine oil contains highly unsaturated fatty acids which are oxidized during storage forming aldehydes and alcohols. The amines and oxidation products result in an unpleasant odor and taste. Oils that initially had no perceptible odor or off taste will develop an unpleasant, odor and/or taste with time.
Oils particularly useful in the present invention are fresh marine oils rich in all-cis-5,8,11,14,17-eicosapentaenoic acid (EPA) and all-cis-4,7,10,13,16,19 docosahexaenoic acid (DHA). These acids, commonly referred to as omega-3 fatty acids, are known to reduce platelet aggregation, thrombotic tendencies and blood viscosity in normal adults. In addition, omega-3 fatty acids have been found to reduce elevated serum cholesterol, triglycerides, cholesterol rich low density lipoproteins and triglyceride rich very low density lipoproteins in adults with elevated serum cholesterol.
Capsules, tablets and liquids are the most common dosage forms for the oral administration of unpleasant edible oils. Many people have difficulty swallowing capsules and tablets. This problem is exacerbated by the larger size tablets and capsules often required in oil based products.
U.S. Pat. No. Re. 18,719 discloses a process for making cod liver oil tablets. The cod liver oil extractives are applied to charcoal in the presence of a volatile solvent and other ingredients. Volatile solvent is removed and the particles made into tablets. Oil content is 7 to 30% of the tablet weight.
U.S. Pat. No. 1,845,370 discloses a stable cod liver oil and water emulsion stabilized with a calcium phosphorous compound and acacia with sugar added to sweeten the composition.
U.S. Pat. No. 1,638,700 discloses a powdered fish oil product which is designed for use as a stock conditioner or vitamin supplying agent or enricher for animal foods. Oil is combined with a mineral carrier such as the non-metallic minerals especially calcium and magnesium groups, as for example, calcium carbonate, calcium palmitrate, calcium lactate, calcium glycolate, calcium saccharate, calcium hydrate, calcium oxide, calcium stearate, or other similar calcium salts or calcium minerals. Minerals of the magnesium group which may be used are magnesium carbonate, magnesium oxide, magnesium silicate, and other magnesium salts or magnesium compounds.
Final fish oil content of the product may be up to 60 percent (60%).
South African Pat. No. 63/809 discloses an aqueous multiple vitamin composition having an oil phase dispersed therein to form an emulsion. The oral phase can be any non-toxic orally acceptable animal or vegetable oil.
Japanese Pat. No. J56169-622 discloses preparing a solid drug containing an oily liquid effective ingredient by absorbing the oil liquid and a nonionic surfactant on a granular powder such as aluminum magnesium hydroxide, magnesium metasilicate aluminate, magnesium oxide and aluminum hydroxide.
U.S. Pat. No. 4,623,489 discloses deodorizing edible oils by refining the oils by deaerating the oil during the degumming steps and the acid-H.sub.2 O washing.
U.S. Pat. No. 4,623,488 discloses refined fish oil produced by (a) preliminary molecular distillation of a mixture of polyhydric alcohol, a monoglyceride and a fish oil to remove volatile components and deodorize fish oil.
U.S. Pat. No. 4,639,367 discloses a foamable, edible oil anhydrous aerosol foam delivery system for solid particulate therapeutic agents. The aerosol foam composition comprises a foamable liquid oil, a foaming agent, a propellant and dispersed solid particles, said particles comprising an active therapeutic agent.
Tablets and capsules solve the unpleasant taste and odor of the oils by avoiding oral contact. The oil being entrapped within the tablet or capsule is physically not available for smell or taste. The limitation of these dosage forms is that they can deliver only small amounts of the oil per dose. The recommended adult dose for castor oil is 5 ml two to four times a day. While the therapeutic dose for marine oil and marine oil concentrates is about 12 to 15 grams per day. Since a large pharmaceutical capsule contains about 1 gram of oil, equal to about 1 ml, the use of capsules would be both inconvenient and expensive. Tablets are capable of delivering even less oil than capsules. A one gram tablet would contain only about 25 to 30 percent oil. In addition, many people have difficulty in swallowing capsules and tablets.
Animal, vegetable and mineral oils produce an oily unpleasant mouthfeel when placed in the mouth. In addition, the unpleasant edible oils of the present invention have, in the case of marine oils, a distinct fishy odor and taste, while vegetable oils such as castor and linseed have an acrid taste and a decidedly nauseating after-taste. Also, the low density of oils often contributes to esophageal reflux. This condition occurs as the oils, floating on the upper surface of the stomach contents, reenter the lower end of the esophagus resulting in a retasting sometimes nauseating effect.
It is desirable therefore to deliver large doses of unpleasant edible oils without the unpleasant odor, taste and mouthfeel problems associated with these oils.